<?phpclass dataCenter {    protected $_list_data = array(        "user",        "banner",        "content",        "server"    );    public function __construct($cacheKey, $cache = false, $session = false)    {        $this->_cacheKey = $cacheKey;        foreach ($this->_list_data as $data_name)        {            $this->$data_name = new $data_name($cacheKey, $cache, $session);        }    }}